, the ottoman empires, spain, russia, britain, each flourished for around 250 years, and this seems to be the space allotted for imperial he generalny. too long a period of power leads to decadence, so the empire goes from the pioneers to the innovators, to the bureaucrats, from exploration on exploitation to decadence, the quest for world approval, the welfare state and squabbles over inherited wealth. and a notable feature, he writes, of the declining nations is the loss of physical energy. he suggests, as does the bible, that the state of a human organism is no different than the family. both recapitulate human individual tendencies, and like the individual human, evolve in predictable directions. the human might, indeed can, live to be 120 years, but no longer, and will decay through predict blg stages as will the family, however well ty -- and the state, however powerful. and now we see we in america are at the outword end of sir john gloves' 250 years, and we see the signs. we have passed through the ages of outburst, conquest, commerce, affluence, intellect, and we've come to